ConDep
ConDep is a open source infrastructure configuration and deployment DSL (Domain Specific Language) specifically targeted to (but not limited to) the Windows Server platform. If your familiar with tools like Chef and Puppet, ConDep does very much the same, but with native support for Windows.
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FAI
Fully Automatic Installation (FAI) is a tool for mass unattended deployment of Linux. You can take one or more virgin PCs, turn on the power, and after a few minutes, the systems are installed and completely configured.
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Instrumental
Instrumental is a real-time, high-scale application and server monitoring tool with intelligent alerts, a powerful query language, and free development accounts.
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jclouds
A Java Library for controlling cloud resources, with various plugins for many popular cloud providers.
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KairosDB
KairosDB is a fast distributed scalable time series database written on top of Cassandra. RESTful JSON-based query/results. Includes flot-based visualization.
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Pallet
A tool to provision and maintain servers across various cloud platforms as well as virtual machine platforms, without any dependencies. Provides cloud and operating system independence.
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SSH KeyBox
An open-source jump box solution with auditing capabilities
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